The aims of this study were (1) to estimate the phenotypic association between different degrees of severity of claw disorders and production, fertility performance, and longevity in Spanish dairy cattle, and (2) to quantify its economic impact at the animal and herd level. In this study, claw data comprised 108,468 trimmings collected between 2012 and 2014 by 25 trimmers from 804 Holstein dairy herds. The claw disorders considered were the 3 most frequent disorders in Spanish dairy herds: dermatitis (DE), sole ulcer (SU), and white line disease (WL). The presence of SU or WL was associated with a significant decrease in milk production and was more important in cows in second or later lactations. A severe lesion of SU or WL lead to twice the milk losses associated with a mild lesion, ranging from 1.47 to 2.66kg/d of energy-corrected milk. The presence of SU or WL during the early lactation period was associated with more days open, fewer inseminations to get pregnant, and longer calving to first service interval (4.83 and 8.0 d longer due to mild and severe lesions of SU, respectively, and 4.94 and 17.43 d longer due to mild and severe lesions of WL, respectively). The occurrence of a case of SU or WL in first lactation had a significant effect on longevity, with severe lesions reducing up to 71 d of productive life. The cost of a mild lesion ranged from $53 to $232 per affected cow and year, whereas the cost of a severe lesion ranged from $402 to $622 per affected cow and year. The annual costs per cow for DE, SU, and WL were $10.80, $50.9, and $43.2, respectively. An average herd with 64 cows had an extra expenditure of $691/yr due to DE, $3,256/yr due to SU, and $2,765/year due to WL. Milk losses, longer calving intervals, and premature culling contributed to more than half of the costs. Therefore, providing this information to farmers could help decide on strategies to reduce the incidence of claw disorders on the farm.

A data file of 225,085 inseminations and 120,713 lactations from 63,160 Holstein cows was analyzed to obtain female fertility economic value according to number of inseminations per service period (INS). Fertility cost (FCOST) was included in a bioeconomic model, taking into account number of doses of semen, hormonal treatments, fertility culling cost, and delayed milk and calf sales. A profit equation was elaborated to estimate fertility cost and profit according to INS. Fertility in Spanish dairy cattle has worsened >10% over the last 14 yr. Days open have increased by about 15 d, and INS has increased from 1.7 to 2.0. A quadratic relationship was found between FCOST and INS. Similar profitability was estimated for cows who needed one or 2 INS, but when >3 INS were needed, profit decreased by >205 (US dollars)/yr per cow. Cows that needed more INS had higher milk yield per lactation, but also had a higher culling risk and lower productive life and lifetime production, therefore, lower profit. Calving interval (CI) and INS economic values were, respectively, -4.90 and -67.32 (US dollars)/yr per cow and per one unit of change. The economic values of productive traits were 4.04, 1.02, and 1.19 (US dollars)/yr per cow and per one unit of change for kg protein, kg fat, and days in milk, respectively. A mature body weight economic value of -0.67 (US dollars)/yr per cow and per kg was estimated. The relative importance of fertility traits with respect to protein was 64% for CI and 24% for INS, although the CI economic value is highly influenced by phenotypic standard deviation considered.

The phenotypic and genetic relationships of 3 locomotion traits with profit, production, longevity, and fertility traits were studied to determine the importance of locomotion traits for dairy producers. Two data sets including official milk records and type classification scores of 62,293 cows, and reproductive records of 24,561 cows from the Basque and Navarra Autonomous Regions were analyzed. Higher scores for feet and legs (FL), foot angle (FA), and rear legs set (RLS) were positively related to production and functional traits, whereas fertility was not significantly affected. The cows that scored the highest for FL were $213/yr more profitable, produced 575 kg more milk per year, and remained in the herd for 307 more functional days than the cows scoring the lowest. Feet and legs was the trait most genetically correlated to profit, although a low value (0.10) was obtained, whereas RLS was the trait most correlated to milk production (0.12). Genetic correlations among FL, FA, RLS, and longevity traits (from -0.10 to 0.05) were low. Quadratic curves were the best fit for both profit and functional herd life for EBV of each of the 3 locomotion traits. Further studies dealing with profitability and lameness, instead of using conformation traits, could be performed directly if a larger data pool of lameness was routinely recorded.

Genetic parameters for lifetime profit and some productive traits were estimated from records of 42,401 Holstein cows with first calving before May 1996 from Navarra and Basque Autonomous Regions of Spain. Profit from the first, first two, and first three lactations were tested as early measures of profitability. Profit prediction was tested for another population of 2127 cows using selection indexes (Type-Production and economic indexes) and multitrait analysis for directly predicting profit from first-lactation records. High genetic correlations of actual profit with estimated profit from the first two or first three lactation records, (0.97 and 0.99, respectively) suggest that lifetime profit can be accurately estimated from data in second lactation. Profit was positively correlated to production traits (0.79 to 0.83), functional herd life (0.38), mature body weight (0.25), and days in milk (0.35), but genetic correlation was found to be close to zero with calving interval. Complicated relationships among profit and economic traits (i.e., calving interval, days in milk, and functional herd life) were found. Although the correlation between calving interval and profit was near zero, calving interval was the most important trait after production in prediction of sire profit by a stepwise regression analysis. Profit breeding values from multitrait analysis obtained higher correlation (0.48) with actual profit than Spanish official Type-Production index ICO (0.44) and economic index MEG (0.46). A correlation of 0.49 between profit breeding values and the economic index MEG2002, where stature and calving interval were included as new traits, was obtained.

This study had 3 objectives: to estimate genetic parameters and predict sires' transmitting abilities for clinical mastitis in a Spanish Holstein population, to propose a methodology for comparing models with different response variables by using a cost-based loss function, and to evaluate alternative genetic evaluation models by using this methodology. On-farm records for clinical mastitis from herds in 3 Spanish regions were analyzed as a binary trait (CM) and as number of episodes (NCM) per lactation. Linear and probit models were fitted for CM, whereas linear and Poisson models were used for NCM. Predictive ability of the models was evaluated by using the average predicted residual sum of squares from cross-validation and an alternative cost-based loss function. The loss function for model comparison was calculated by using average mastitis costs depending on the NCM and average cost per infected lactation. The average cost per infected lactation was $345.58, whereas the cost per lactation ranged from $204.86 to $985.44 for lactations with 1 to 5 cases, respectively. Management and hygiene practices on individual farms had a large impact on clinical mastitis because the herd-year variance was larger than that of other random effects considered. The sire variance was significantly different from zero, confirming that genetic variation exists for clinical mastitis. Estimates of heritability for CM using the linear and probit models were 0.07 and 0.10 on the underlying scale, respectively. For NCM, the estimate of heritability for the linear model was 0.10 and estimates for the Poisson model evaluated at the mean and the median of lambda on the underlying scale were 0.09 and 0.07, respectively. Regarding ranking of sires, the definition of response variable (CM or NCM) was of greater importance than the choice of statistical model. Cross-validation results indicated that models with the best fit for CM and NCM were the probit model and the linear model, respectively. However, a comparison across all models using the alternative cost-based loss function showed that using NCM as a response variable with a Poisson model provided the most accurate predictions of future costs associated with clinical mastitis.

Genetic parameters and relationships were estimated for profit and type traits for Spanish Holstein cows. In this study, 46,316 cows with official production and type data from Navarra and Basque autonomous regions of Spain were used to calculate profit per cow and year of productive life. Data from 239 Basque Autonomous Region herds in year 1995 were considered to obtain average prices system for yield, meat, feeding, and housing costs. An average cow had a net profit of 78.56 euros per year of productive life, with 7334 kg of milk, 3.85 lactations and 28.0 mo of age at first calving. Heritability of profit was 0.25. Genetic correlations between profit and almost all conformation traits were low to moderate, from 0.12 for leg side view to 0.37 for suspensory ligament while stature, body depth, and udder depth had close to zero correlations with profit. Significant quadratic relationships were found between breeding values for profit and feet and legs, foot angle, fore-udder attachment, rear-udder height and udder depth. The most influential type trait on profit adjusted for production was feet and legs. Animals with negative breeding values for legs were not less profitable than another with zero value, but positive values increased profit per cow and year with a quadratic and positive relationship. Other traits affecting profit out of production and longevity, such as fertility and mastitis, should be considered in future studies.

The aim of this work was to study the effect of parity order and reproductive management systems on rabbit production performance. A total of 73 rabbit does (I group) were submitted to a 35-day intensive rhythm [artificial insemination (AI) on day 4 post-partum (pp) and weaning at 25 days of lactation], and 108 rabbit does (SI group) were submitted to a 42-day semiintensive rhythm (AI on day 11 pp and weaning at 35 days of lactation) during 9 months. Primiparous does had the lowest live body weight at parturition (P<0.0001) and at 21 days of lactation (P< 0.0001). They also had lower milk production (P< 0.0001) than does with later parities. I group animáis needed a higher number of AI than SI group to become pregnant (1.70 ± 0.03 vs. 1.39±0.03; P<0.0001: especially after the third). Prolificacy was not affected by the management system. Parturition interval (PI) was longer than expected in both groups [56.0± 1.4 and 50.9± 1.38 days in I and SI groups, respectively (P<0.05)]. Mean productivity, estimated as number of weaned rabbits per female and year, was 12 kits higher in rabbit does of the SI group (P<0.05). From the third parturition onward, an increase in live body weight of kits at different ages was observed. At 21 (P<0.05) and 25 days of age (P<0.01), kits from the I group rabbit does weighed more than those from the SI group; however, the latter showed a higher weight at 35 (P<0.05) and 60 days of age (P<0.05). Rabbit does with two or three parturitions had higher litter size at 21 and 25 days of age (P<0.0001 and P<0.001, respectively). Kit mortality between 21 and 25 days of age and between 35 and 60 days of age was not affected by treatments but was higher in the I group between 25 and 35 days (18.2 vs. 5.03% in the I and SI groups, respectively; P<0.0001) and as age of does increased (P<0.05). In light of these results, we could conclude that long term doe reproductive performance is negatively affected and litter viability decreased when using intensive compared to a semi-intensive reproductive management.

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